Conic from 2 Positions
KeyCreator \ Create \ Conic \ Conic-from-2-Positions

Location: Create>Conic>Conic from 2 Positions

Use this feature to create a conic based on indicated positions for the start and end points of the conic, the slope of the conic at the start and end positions, and a rho value that determines the type of conic. Rho is the ratio of the length of line segment R to the length of line segment T.

When creating this type of conic, keep the following things in mind:

  • You cannot indicate coincident positions.

  • Definition of the conic must include the slope of the conic at one or two of the indicated positions.

  • You cannot direct the tangent vector that defines the slope of the conic at a selected position toward any of the other positions that you indicated in defining the entity.

  • In 2D construction mode, the indicated points and slopes are projected to the current construction plane. It creates the conic in the current construction view, at the depth that was active when you defined the slope at the end point.

  • In 3D construction mode, the conic is created in the plane defined by the two indicated points and the first tangent vector. The second tangent vector is projected to this plane.

<p class="Body-Text> The following figure illustrates the relationship between the rho value and the conic.


The following list illustrates the relationship between the rho value and the
conic type.

Value

Conic Type

0.0 < rho < 0.5 
Ellipse
rho = 0.5 
Parabola
0.5 < rho < 1.0
Hyperbola

Using the Function:

  1. Select Conic from 2 Positions from the Create>Conic submenu.

  2. Indicate start and end positions for the conic.

  3. Enter a rho value. The value must be greater than zero and less than one.

Define the slope of the conic for the start and end positions.